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An efficient synthetic method for the production of stabilized cyclo-olefin polymer (COP) latexes catalyzed by a well-defined ruthenium carbene catalyst in aqueous solution is reported by Hoang The Ban, Masahiro Shigeta, Tsutomu Nagamune, and Mitsugu Uejima on page 4584. The COP latexes exhibit an exceptionally high compatibility with well-dispersed carbon nanotubes (CNTs) in aqueous solution due to strong ππ interactions between the graphitic surfaces of the CNTs with the CC bonds located on the COP main chains. Accordingly, a binary blending of these two well-dispersed colloidal systems in aqueous solution leads to the fabrication of highly homogeneous COP/CNT composite nanoparticles that possess high electrical conductivities due to the presence of uniformly CNT-based networks made from individually interconnected CNTs deposited on the interface of COP nanoparticles as observed in the cover image.

The solid state self-assembly of single-walled carbon nanotubes (SWCNTs) and pyrenyl-terminated poly(γ-benzyl-L-glutamate)s (py-PBLG) is presented by Haoyu Tang and Donghui Zhang on page 4489. Py-PBLGs are prepared by controlled polymerization of γ-benzyl-L-glutamic acid based N-carboxyanhydride using an amine initiator. Py-PBLGs effectively enhance the dispersion of SWCNTs in organic solvents and the PBLG solid through π-π interactions. The cover image depicts the disparate orientation of SWCNTs relative to the PBLG main chain, which is dictated by the polymer conformation (α-helix and β-sheets) and the location of pyrenyl moieties. The relative packing structure also affects the intermolecular interaction among the PBLGs differently.

Single-walled carbon nanotubes (SWCNTs) were shown to significantly enhance the hexagonal packing order of the poly(γ-benzyl-l-glutamate) (PBLG) rods in the solid state. By contrast, the lamellar packing order of the PBLG β-sheets consisting of short PBLG chains is weakened. The differing effect has been attributed to the disparate orientation of SWCNTs relative to the PBLG main chain, which is dictated by the polymer conformation and the location of pyrenyl moieties.

The hydrophobic segment of a designed amphiphilic triblock copolymer bearing multiple hydrogen bonding sites at the center of the polymer backbone was promoted due to complementary H-bonding interaction with a hydrophobic DAD-functionalized polymer. In water, hydrophobic interaction supported self-aggregation. The aggregates in aqueous media were relatively stable and uniform in size, which most likely stems from the intermolecular complementary hydrogen bond interaction at the polymer chain centers.

Novel methacrylate and acrylate monomers with an isothiocyanate structure were synthesized using 2-isothiocyanatoethyl methacrylate (ITEMA) and 2-isothiocyanatoethyl acrylate (ITEA). Their radical polymerizations were examined, respectively. Isothiocyanato groups in the monomers did not react with water in an acetone solution at 60 °C for 24 h, showing their tolerance to water. Because of this water-stable characteristic of isothiocyanato groups, ITEMA and ITEA can be polymerized in a water-containing solvent.

Poly(1-vinyl-3-alkylimidazolium hydrogen carbonate) (poly([NHC(H)][HCO3])) can be readily accessed and serve as air-stable polymer-supported pre-catalysts for organocatalyzed molecular reactions, including benzoin condensation, transesterification, and cyanosilylation. The in situ generation of related polymer-supported N-heterocyclic carbenes (poly(NHC)s), occurs by a loss of H2O and CO2 in solution. Recarboxylation of poly(NHC)s allows recycling of polymer precursors.

Two new low-band gap selenophene-based polymers were synthesized successfully. The differences of optoelectronic and photovoltaic properties and space-charge-limited currents were compared with those of related thiophene-based polymers. Organic photovoltaic devices, based on blends of these polymers and PC71BM, were fabricated; the maximum power conversion efficiency of the device based on PSPSBT and PC71BM was 3.1%.

A simple route to POSS containing organic–inorganic hybrid nano-objects with different morphologies through polymerization and (or) cooling-induced block copolymer self-assembly was described. The cooling procedure and chain length of macro-CTA was proven to be a crucial step to generate particles with a unique morphology.

A facile synthetic route has been developed to produce poly(l-tryptophan) by the polycondensation of N-phenoxycarbonyl-l-tryptophan. The polycondensation proceeded smoothly at 60 °C in N,N-dimethylacetamide (DMAc) in the presence of amines (n-butylamine, diethylamine, and triethylamine). The structural analysis by MALDI-TOF mass spectrometry revealed that n-butylamine or diethylamine was successfully incorporated into the chain end of the polypeptide. Furthermore, synthesis of diblock copolymer by utilizing amine-terminated poly(ethylene glycol) as a source of the polyether segment was established.

A series of amphiphilic A4B4 star-shaped copolymers (PEO)4(PCL)4, (PEO)4(PS)4, and (PEO)4(PtBA)4 were successfully synthesized using the core-first strategy by combination of ring-opening polymerization and atom transfer radical polymerization with thiol–ene reaction. This synthetic method might be a versatile one for various AnBn (n≥3) star-shaped copolymers with defined structure and compositions.

A highly efficient and environmentally benign synthetic method for the production of cyclo-olefin copolymer latexes using an emulsion ring opening metathesis polymerization catalyzed by the 2nd generation Grubbs catalyst in aqueous solution was reported. The as-prepared cyclo-olefin copolymer latexes show exceptionally high compatibility with a well-dispersed carbon nanotube in aqueous solution. A binary blending of these stabilized colloidal systems in aqueous solution thus led to the fabrication of highly electrical conductive cyclo-olefin copolymer/carbon nanotube composite nanoparticles.

Fluorescent monomers were prepared and introduced to polystyrene microsphere chemosensors. The microspheres could detect Hg2+ ions by the change of color and fluorescence. Moreover, the microspheres could separate Hg2+ ions by centrifugation.

The synthesis of functional polymer particles in organic media has grown in importance because of the large advance of all electronic papers applications. The use of a NMRP macroinitiator soluble in apolar media shows great efficiency in producing functional polymer particles in one step, bearing ionizable groups like pyridine or carboxylic acid. The process allows synthesis in a controlled way, producing very stable particles on a wide scale (75 nm to 20 μm).

Original series of well-defined composite hybrid hydrogels are presented and synthesized by frontal polymerization. Comparison between two different acidic media is performed and there is evidence that indicates that the amount of the inorganic moiety affects the hydrophilicity, as well as the thermal stability of the composite. Therefore, swelling ratio, thermal, contact angle, and morphology studies are performed and the results of these studies are highlighted.

Photo-initiated thiol–ene is demonstrated as an alternative “click” reaction to synthesize thermoresponsive poly(N-isopropylacrylamide) “model networks.” RAFT-synthesized poly(N-isopropylacrylamide) with thiol and ene moieties are used as network precursors. The ability of these polymers to crosslink is found to be dependent on steric effects of the polymer end groups and the sensitivity of thiol groups to air, which could potentially lead to oxidation to form disulfides. As a result, the ene moieties provide more success in preparing “model networks.”

Imide-containing diene and dithiol monomers were synthesized and used in thiol–ene polymerizations that yield poly(imide-co-thioether)s. These linear polymers exhibit limited solubility in various organic solvents and show increased glass transition temperature (Tg) as the imide content increases.

Poly(glycolic acid) and poly(ɛ-caprolactone) brushes were grown from hydroxy-terminated silicon surfaces via ring opening polymerization using tin (octanoate) as the catalyst. Poly(ɛ-caprolactone) brushes grew thicker at elevated temperatures but the thickest poly(glycolic acid) brushes grew at room temperature. The confined surface polyester brushes only degraded under neutral or basic conditions. Through a blocking experiment, the terminal hydroxyl groups of these brushes were demonstrated to be essential to the degradation process, indicating a preferential backbiting mechanism.

Soluble, thermally stable, and photoresponsive polyamides are obtained via the Yamazaki polyaddition between a pentamethylated norbornadiene dicarboxylic acid and several aromatic diamines. Characterization by 1H and 13C NMR, SEC, FTIR, DSC, TGA, and viscosimetry is performed. The photochemical isomerization of the norbornadiene units into quadricyclane ones is studied by UV/Vis spectroscopy. The thermal release of the stored energy associated to the reverse transformation of quadricyclane groups into norbornadiene ones is about 90–95 kJ mol−1 as measured by DSC.

Polysulfone with terminal benzyl bromide groups was used as a bifunctional macroinitiator for atom transfer radical polymerization of 2,3,4,5,6-pentafluorostyrene. The fluorostyrene blocks of the ABA triblock copolymers were selectively and quantitatively phosphonated with tris(trimethylsilyl)phosphite and hydrolyzed to form poly(2,3,5,6,-tetrafluorostyrene-4-phosphonic acid). Solvent cast copolymer membranes had a high thermal stability, and showed a nanophase-separated morphology and high proton conductivity at 80 mS cm−1 at 120 oC under fully hydrated conditions.

A Friedel–Crafts-type termination, a common side reaction, of cationically prepared living polymers proved a powerful reaction for the highly efficient synthesis of graft copolymers. A well-defined graft copolymer was obtained from the reaction of pendant alkoxynaphthyl groups, more nucleophilic than a phenyl counterpart, in poly(vinyl ether) with a living polymer of p-acetoxystyrene, the ideal living cationic polymerization of which was performed for the first time using SnCl4 in the presence of ethyl acetate.

Relationships between side group structures of plant-derived aldehydes and their copolymerization behaviors with vinyl ether were investigated. Conjugated aldehydes were cationically copolymerized in alternating fashion, some of which were controlled to produce copolymers with well-defined structures. The product alternating copolymers were selectively degradable by acid hydrolysis into other conjugated aldehydes. Judging from copolymerization results using various plant-derived aldehydes with acyclic or cyclic structures, bulkiness and electron-donating ability of side groups would be crucial for copolymerization behaviors.

A novel class of ladder-type polymer named polydibenzoyl[b,f][1,5]diazocine and polydimethoxybenzoyl[b,f][1,5]diazocines based on a diazocine unit were developed for electrochemical actuator materials. The polydiazocines may exhibit a conformation change from zigzag or helix conformation to planar structure of their diazocine ring upon redox processes. This may simulate electrical response of the muscle.

The synthesis and characterizations of a series of statistical copolymers of benzyl methacrylate with 2–11 mol% 9-(4-vinylbenzyl)-9H-carbazole is examined. The synthesis via nitroxide-mediated polymerization using BlocBuilder as the initiator at 90 °C was demonstrated to be relatively well controlled. These copolymers exhibit fluorescent and thermoresponsive properties, as well as an interesting phase separation–triggered fluorescent enhancement behavior in a hydrophobic ionic liquid (C2mim)(NTf2), which are comprehensively studied and discussed.